Fertilizer Drying, Nitrogen Loss in Drying of Ammoniated Superphosphates and Mixed Fertilizers

Abstract

Laboratory experiments were carried out on drying of ammoniated superphosphates and mixed fertilizers to determine under what conditions loss of nitrogen and potassium and reversion of available phosphorus pentoxide would occur.Both storage-cured and quick-cured superphosphate were used for ammoniation. Sources of nitrogen included aqueous ammonia, ammonium nitrate, ammonium sulfate, and ammoniating solution.

Fertilizer Technology, Countercurrent Versus Cocurrent Drying of Granulated Mixed Fertilizers

“…The cocurrent dryer is more widely used than the countercurrent dryer (3), because it does not overheat the material when exposed to the hot inlet (throat) gases from the furnace. Overheating is undesirable because it can result in nitrogen loss from some of the materials as well as fume formation (1,8).…”

“…Previous investigations have considered various aspects of fertilizer drying (1,4,5). This paper reports the results of laboratory and pilot plant scale tests conducted to determine the causes of visible dryer exhaust fume and to compare cocurrent and countercurrent drying.…”